This contract is in support of activities conducted by the NCI's Division of Cancer Control and Population Sciences Applied Research Program as part of the National Collaborative on Childhood Obesity. The National Collaborative on Childhood Obesity Research (NCCOR) is a partnership of the Centers for Disease Control and Prevention, the National Institutes of Health, the U.S. Department of Agriculture, and the Robert Wood Johnson Foundation. NCCOR seeks to improve the efficiency, effectiveness and application of childhood obesity research by developing common measures and methods, evaluating and identifying effective interventions, and assessing policy and environmental changes related to childhood obesity.